US9012801B2 - Flexible shunt for vacuum circuit breaker - Google Patents

Flexible shunt for vacuum circuit breaker Download PDF

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Publication number
US9012801B2
US9012801B2 US13/358,436 US201213358436A US9012801B2 US 9012801 B2 US9012801 B2 US 9012801B2 US 201213358436 A US201213358436 A US 201213358436A US 9012801 B2 US9012801 B2 US 9012801B2
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United States
Prior art keywords
connecting portion
terminal
flexible
shunt
clamp
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US13/358,436
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US20120199557A1 (en
Inventor
Seung Pil Yang
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LS Electric Co Ltd
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LSIS Co Ltd
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Assigned to LSIS CO., LTD. reassignment LSIS CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: YANG, SEUNG PIL
Publication of US20120199557A1 publication Critical patent/US20120199557A1/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
    • H01H33/66—Vacuum switches
    • H01H33/6606—Terminal arrangements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/58—Electric connections to or between contacts; Terminals
    • H01H1/5822—Flexible connections between movable contact and terminal
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/58—Electric connections to or between contacts; Terminals
    • H01H1/5822—Flexible connections between movable contact and terminal
    • H01H2001/5827—Laminated connections, i.e. the flexible conductor is composed of a plurality of thin flexible conducting layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
    • H01H33/66—Vacuum switches
    • H01H33/6606—Terminal arrangements
    • H01H2033/6613—Cooling arrangements directly associated with the terminal arrangements

Definitions

  • This disclosure relates to a vacuum circuit breaker, and particularly, to a flexible shunt for providing a conductive path between a movable electrode side and a main circuit terminal in a vacuum circuit breaker.
  • a vacuum circuit breaker is a kind of electric power equipment for opening or closing a conductive path of an ultrahigh voltage to high voltage of a power station or an electric power substation and protecting a circuit and an electric load side devices connected to the circuit by breaking the circuit upon occurrence of a fault current on the circuit.
  • a vacuum circuit breaker is embedded in a distributing board, which includes an instrument and monitoring device such as a digital relay, and a plurality of circuit breakers, for monitoring states of the electric power and lines.
  • vacuum circuit breaker Since the vacuum circuit breaker is typically used by being embedded in the distributing board, a pull-out type vacuum circuit breaker having a carriage, which is movable for facilitation of installation and maintenance thereof.
  • the pull-out type vacuum circuit breaker roughly includes, for each of three phases (poles), a circuit breaker main body (abbreviated as main body hereinafter) provided with a contact part called as a vacuum interrupter, a switching mechanism for opening or closing the contact part, and a terminal part electrically connected to the contact part, the main body movable by the carriage having wheels, and a cradle for supporting the main body, the cradle having a first terminal part connected to the terminal part of the main body, and a second terminal part electrically connected to an external electric power circuit, the cradle fixed into a power distributing board.
  • the cradle is a housing having the first terminal part and the second terminal part, and less relevant to the present disclosure. So, the cradle will not be illustrated and described in detail.
  • a main body 100 may be installed on a carriage having wheels (no reference number given) to be movable back and forth.
  • the main body 100 may include a front cover 10 , a main body housing 20 , a main circuit part 30 and terminal parts 32 a and 40 a .
  • the terminal parts 32 a and 40 a may include an upper terminal 32 and a lower terminal 40 to be explained with reference to FIG. 2 , and finger contactors of terminal end portions (no reference numeral given) of the upper terminal 32 and the lower terminal 40 .
  • the main body 100 may be movable to a connected position at which the terminal parts 32 a and 40 a are connected to the first terminal part of the cradle, a test position at which the terminal parts 32 a and 40 a are separated from the first terminal part of the cradle due to the main body 100 being drawn out by the carriage but a electric power supply and signal line connection are maintained with respect to a controller (i.e., a controller (no reference numeral given) located at the rear of the front cover 10 of FIG.
  • a controller i.e., a controller (no reference numeral given) located at the rear of the front cover 10 of FIG.
  • OCR Over Current Relay
  • the present disclosure relates to a flexible conductor, so-called a flexible shunt, which provides a flexible electric connection unit for electrically connecting a movable shaft, which is connected to a movable contact, and a terminal and simultaneously allows for movement of the movable shaft.
  • a flexible shunt which provides a flexible electric connection unit for electrically connecting a movable shaft, which is connected to a movable contact, and a terminal and simultaneously allows for movement of the movable shaft.
  • a main circuit part 30 having the related art flexible shunt includes a vacuum interrupter 33 as a contact part, an upper terminal 32 and a lower terminal 40 electrically connected to a stationary contact 34 and a movable contact 35 of the vacuum interrupter 33 , respectively, a movable shaft 35 a (so-called movable electrode) 35 a , a connection rod 41 and a push rod 42 acting together as a vertical driving unit to vertically drive the movable contact 35 to a connected position where the movable contact 35 contacts the stationary contact 34 or a connected position where the movable contact 35 is separated from the stationary contact 35 , a link 44 acting as a driving unit disposed at the main body side of FIG.
  • a reference number 31 designates a main circuit part housing as a housing for accommodating those components of the main circuit part 30 .
  • the flexible shunt 38 ′ which electrically connects the movable shaft 35 a connected to the movable contact 35 to the lower terminal 40 , is configured by twisting several strands of copper wires or stacking and pressing several sheets of copper thin plates.
  • the related art flexible shunt 38 ′ caused an increase in the size of the vacuum circuit breaker due to the increase in its length, which resulted in an increase in a fabricating cost of the vacuum circuit breaker.
  • an aspect of the detailed description is to provide a flexible shunt for a vacuum circuit breaker, capable of decreasing a straight length and increasing flexibility with increasing a thickness thereof within a predetermined accommodation space.
  • a flexible shunt for a vacuum circuit breaker having a vacuum interrupter, a movable shaft, a heat sink, a clamp to connect the heat sink to the movable shaft, and a terminal connected to a power source side or load side electric circuit
  • the flexible shunt comprising: a pair of conductive plates, wherein each of the conductive plates comprises:
  • each of the clamp connecting portion and the terminal side connecting portion may comprise a plurality of coupling hole portions for allowing coupling of fixing members including screws.
  • the flexible shunt may further comprise a shunt fixing block interposed between the terminal side connecting portion and the terminal to fix the terminal side connecting portion to the terminal, the shunt fixing block being made of a conductive material.
  • each of the conductive plates may comprise a plurality of electrically conductive thin plates that are stacked and pressed.
  • FIG. 1 is a perspective view showing an outer appearance of a main body for a typical pull-out type vacuum circuit breaker to which a flexible shunt is to be applied;
  • FIG. 2 is a longitudinal sectional view of a main circuit part for the vacuum circuit breaker, which shows a flexible shunt and related components according to the related art;
  • FIG. 3 is a longitudinal sectional view showing a flexible shunt and related components of a main circuit part in a vacuum circuit breaker in accordance with one exemplary embodiment of this disclosure, which shows a contact state between contacts;
  • FIG. 4 is a longitudinal sectional view showing the flexible shunt and the related components of the main circuit part in the vacuum circuit breaker, which shows a separated state between the contacts;
  • FIG. 5 is a perspective view showing the flexible shunt of the vacuum circuit breaker.
  • FIG. 1 A vacuum circuit breaker, to which a flexible shunt according to the present disclosure, has been shown in FIG. 1 , so description thereof will not be repeated.
  • a main circuit part 30 having a flexible shunt may comprise a vacuum interrupter 33 as a contact part, an upper terminal 32 and a lower terminal 40 electrically connected to a stationary contact 34 and a movable contact 35 of the vacuum interrupter 33 , respectively, a movable shaft 35 a (so-called movable electrode) 35 a , a connection rod 41 and a push rod 42 acting together as a vertical driving unit to vertically drive the movable contact 35 to a connected position where the movable contact 35 contacts the stationary contact 34 or a connected position where the movable contact 35 is separated from the stationary contact 35 , a link 44 acting as a driving unit disposed at the main body side of FIG.
  • a reference number 31 designates a main circuit part housing as a housing for accommodating those components of the main circuit part 30 .
  • the flexible shunt 38 may comprise a pair of conductive plates 38 a and 38 b installed to face each other.
  • Each of the conductive plates 38 a and 38 b may be configured by stacking and pressing a plurality of electrically conductive thin plates.
  • Each of the conductive plates 38 a and 38 b constructing the flexible shunt 38 may comprise a clamp connecting portion 38 a 1 or 38 b 1 , a terminal side connecting portion 38 a 3 or 38 b 3 , and a flexible curved portion 38 a 2 or 38 b 2 .
  • the clamp connecting portion 38 a 1 or 38 b 1 may be connected to the clamp 36 , and configured as a flat conductive member.
  • the terminal side connecting portion 38 a 3 or 38 b 3 may be connected to a terminal side, namely, the lower terminal 40 and configured as a flat conductive member.
  • the clamp connecting portion 38 a 1 or 38 b 1 and the terminal side connecting portion 38 a 3 or 38 b 3 may comprise a plurality of coupling hole portions 38 c and 38 d , respectively, for allowing coupling of fixing members including screws.
  • the flexible curved portion 38 a 2 or 38 b 2 may be connected between the clamp connecting portion 38 a 1 or 38 b 1 and the terminal side connecting portion 38 a 3 or 38 b 3 , and configured to be projected outwardly.
  • the flexible shunt 38 may further comprise a shunt fixing block 39 made of a conductive material and interposed between the terminal side connecting portion 38 a 3 or 38 b 3 and the lower terminal 40 to connect the terminal connecting portion 38 a 3 or 38 b 3 to the lower terminal 40 . Accordingly, even if there is a height difference between the terminal side connecting portion 38 a 3 or 38 b 3 and the lower terminal 40 , the height difference can be overcome by virtue of the shunt fixing block 39 , so as to facilitate the flexible shunt 38 and the lower terminal 40 to be electrically and mechanically connected to each other.
  • the flexible shunt 38 comprises the pair of conductive plates 38 a and 38 b .
  • Each of the conductive plates 39 a and 38 b comprises the flexible curved portion 38 a 2 or 38 b 2 at the middle thereof, which provides an increased surface length of the flexible shunt 38 although its straight length is short.
  • the flexible shunt can maintain flexibility by the long surface length due to the flexible curved portion 38 a 2 or 38 b 2 at the middle of the conductive plate 38 a or 38 b , in spite of an increase in thickness. Consequently, the clamp connecting portion 38 a 1 or 38 b 1 connected to the clamp 36 coupled to the movable shaft 35 a can be flexibly movable.
  • the clamp connecting portion 38 a 1 or 38 b 1 and the terminal side connecting portion 38 a 3 or 38 b 3 are provided with the plurality of coupling hole portions 38 c and 38 d , respectively, for allowing connection of the fixing members including the screws. Therefore, it can be effective to facilitate connection between the clamp 36 and the lower terminal 40 .
  • the flexible shunt 38 for the vacuum circuit breaker according to the present disclosure may further comprise the shunt fixing block 39 made of the conductive material and interposed between the terminal side connecting portion 38 a 3 or 38 b 3 and the lower terminal 40 . Accordingly, it is possible to overcome the height difference between the terminal side connecting portion 38 a 3 or 38 b 3 of the flexible shunt 38 and the lower terminal 40 , thereby facilitating the electric connection between the flexible shunt 38 and the lower terminal 40 .
  • each conductive plate 38 a , 38 b constructing the flexible shunt 38 is configured by stacking and pressing a plurality of electrically conductive thin plates. Hence, the flexible shunt 38 can exhibit excellent flexibility as compared to the thickness thereof.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • High-Tension Arc-Extinguishing Switches Without Spraying Means (AREA)
  • Trip Switchboards (AREA)
  • Breakers (AREA)
US13/358,436 2011-02-08 2012-01-25 Flexible shunt for vacuum circuit breaker Active 2033-05-04 US9012801B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2011-0011249 2011-02-08
KR1020110011249A KR101150334B1 (ko) 2011-02-08 2011-02-08 진공차단기의 플렉서블 션트

Publications (2)

Publication Number Publication Date
US20120199557A1 US20120199557A1 (en) 2012-08-09
US9012801B2 true US9012801B2 (en) 2015-04-21

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Family Applications (1)

Application Number Title Priority Date Filing Date
US13/358,436 Active 2033-05-04 US9012801B2 (en) 2011-02-08 2012-01-25 Flexible shunt for vacuum circuit breaker

Country Status (7)

Country Link
US (1) US9012801B2 (de)
EP (1) EP2485229B1 (de)
JP (1) JP2012164652A (de)
KR (1) KR101150334B1 (de)
CN (1) CN102637549B (de)
ES (1) ES2567191T3 (de)
RU (1) RU2504855C2 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150034598A1 (en) * 2012-04-25 2015-02-05 Hyundai Heavy Industries Co., Ltd. Structure for preventing eccentricity of movable contact in vaccum circuit breaker

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Publication number Priority date Publication date Assignee Title
EP2551879B1 (de) * 2011-07-27 2014-07-09 ABB Technology AG Stößelanordnung für Schutzschalter
KR200473205Y1 (ko) 2012-12-28 2014-06-16 엘에스산전 주식회사 진공차단기 주회로부의 플렉시블 션트
CN103198969A (zh) * 2013-03-19 2013-07-10 启东德佳电器配件有限公司 一种改进的真空断路器
US9824837B2 (en) * 2014-01-24 2017-11-21 Yazaki Corporation Service plug
CN113838687A (zh) * 2020-06-24 2021-12-24 施耐德电器工业公司 具有辅助分流组件的分断单元和双电源转换开关

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US3542987A (en) 1968-03-18 1970-11-24 Burndy Corp High-current switch with secondary contact pin coupled in offset relationship to principal contact
US4144554A (en) 1976-12-08 1979-03-13 Square D Company Circuit breaker bolt-on flexible connector
SU653649A1 (ru) 1977-01-06 1979-03-25 Предприятие П/Я Р-6409 Система регулировани давлени дл электрохимического генератора с газообразными реагентами
GB1590698A (en) 1976-12-08 1981-06-10 Square D Co Circuit breaker assembly
US4384179A (en) * 1981-02-12 1983-05-17 Westinghouse Electric Corp. Stiff flexible connector for a circuit breaker or other electrical apparatus
CN1072384A (zh) 1992-05-12 1993-05-26 程志明 重力加速器
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KR100996791B1 (ko) 2008-04-10 2010-11-25 엘에스산전 주식회사 진공차단기의 주회로 단자 어셈블리
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US4144554A (en) 1976-12-08 1979-03-13 Square D Company Circuit breaker bolt-on flexible connector
GB1590698A (en) 1976-12-08 1981-06-10 Square D Co Circuit breaker assembly
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150034598A1 (en) * 2012-04-25 2015-02-05 Hyundai Heavy Industries Co., Ltd. Structure for preventing eccentricity of movable contact in vaccum circuit breaker

Also Published As

Publication number Publication date
RU2504855C2 (ru) 2014-01-20
ES2567191T3 (es) 2016-04-20
RU2012104228A (ru) 2013-12-10
CN102637549B (zh) 2015-04-01
KR101150334B1 (ko) 2012-06-08
EP2485229B1 (de) 2016-01-13
EP2485229A1 (de) 2012-08-08
US20120199557A1 (en) 2012-08-09
JP2012164652A (ja) 2012-08-30
CN102637549A (zh) 2012-08-15

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